Counting, analysing and reporting exacerbations of COPD in randomised controlled trials
S D Aaron, D Fergusson, G B Marks, S Suissa, K L Vandemheen, S Doucette, F Maltais, J F Bourbeau, R S Goldstein, M Balter, D O’Donnell, M FitzGerald
Thorax Feb 2008, 63 (2) 122-128; DOI: 10.1136/thx.2007.082636